circuitpython/tests/basics/fun_kwvarargs.py
David Lechner 783b1a868f py/runtime: Allow multiple *args in a function call.
This is a partial implementation of PEP 448 to allow unpacking multiple
star args in a function or method call.

This is implemented by changing the emitted bytecodes so that both
positional args and star args are stored as positional args.  A bitmap is
added to indicate if an argument at a given position is a positional
argument or a star arg.

In the generated code, this new bitmap takes the place of the old star arg.
It is stored as a small int, so this means only the first N arguments can
be star args where N is the number of bits in a small int.

The runtime is modified to interpret this new bytecode format while still
trying to perform as few memory reallocations as possible.

Signed-off-by: David Lechner <david@pybricks.com>
2022-03-31 16:59:30 +11:00

39 lines
498 B
Python

def f1(**kwargs):
print(kwargs)
f1()
f1(a=1)
def f2(a, **kwargs):
print(a, kwargs)
f2(1)
f2(1, b=2)
def f3(a, *vargs, **kwargs):
print(a, vargs, kwargs)
f3(1)
f3(1, 2)
f3(1, b=2)
f3(1, 2, b=3)
def f4(*vargs, **kwargs):
print(vargs, kwargs)
f4(*(1, 2))
f4(kw_arg=3)
f4(*(1, 2), kw_arg=3)
# test evaluation order of arguments
def f5(*vargs, **kwargs):
print(vargs, kwargs)
def print_ret(x):
print(x)
return x
f5(*print_ret(["a", "b"]), kw_arg=print_ret(None))